Draize test

The Draize test is a test performed on animals to test for acute toxicity in cosmetics and common household products. It was named after Dr. John Henry Draize, a toxicologist with the U.S FDA. He was the principal author of a report that came out in 1944 that outlined the basic features of this test to provide an idea of the irritancy of the tested substance. This technique was then used by the FDA to assess the safety for a number of products including sunscreens and insecticides. Even though John Draize never personally attached his name to the technique, assessment of irritancy are called Draize tests. Depending on the target organ of the test, the Draize test may be called the ‘Draize Eye Test’ or the ‘Draize Skin Test’.

The Draize Eye Test

In the Draize eye test, 0.5 ml or 0.5 mg of a substance is applied to an animal’s eye. The substances which are being tested for eye irritation potential range from liquid to granules, powders and flakes. The animals being tested are observed at specific intervals for hours or days, sometimes even up to two weeks. The lab technicians record any redness, swelling, discharge, ulceration or hemorrhaging, blindness or discharge from the eyes of the test animals.

The Draize eye test is most commonly performed on albino rabbits as they have large, sensitive eyes and the structure of their tear ducts prevents tears from washing away the foreign substance. Also, using rabbits is cost effective.

To conduct the test, the rabbits are placed in restraining stocks and often clips are placed on their eyelids. It has been reported that many of the rabbits strangle themselves in attempts to free themselves of the restraints and their behavior indicates that they are in extreme pain and discomfort during the test.

The Argument against the Draize test

Recently, the animal testing and the Draize test in particular have come under a great deal of scrutiny and have the subject of controversial debate. The issue of animal testing has been given a lot of importance thanks to the work of various animal rights organizations. With more media coverage, animal testing has been shown as an extremely cruel practice.

The Draize eye test in particular, has been heavily criticized for its animal cruelty. Notably, it has also been criticized by the scientific community. The test is strictly observational and does not offer any treatment and does not seek antidotes. Health care professionals claim that Draize data does not help them in the treatment of patients. The biggest criticism of the Draize test is that it is considered unreliable and imprecise.

In 1971, an industry-funded study was conducted by Weil and Scala of the Mellon Institute of Pittsburgh and the Medical Research Division of Esso. The study was conducted in 25 different laboratories and revealed extreme variations in the the way yiou make me move a lack of fine discrimination – that is, it could only be effectively used to crudely distinguish irritants from non irritants. The reproducibility of results from different laboratories in routine testing was found to be questionable. These results also question the applicability of Draize eye test results to the human situation.

Questioning the use of Rabbits in the Draize Eye Test

In 2001, Dr. Kirk Wilhelmus, a professor in the Department of Ophthalmology at Baylor College of Medicine, conducted a comprehensive review of the Draize Eye test. According to his report, there are too many differences between the rabbit eye and the human eye and indicate that testing substances on rabbits may not be accurate prediction of the effect on humans. The significant differences between rabbit eye and human eye are:

• Rabbits have a nictitating (winking) membrane (third eyelid), which has an unclear effect on elimination of foreign materials
• The rabbit mean corneal thickness is .37 mm, while that of man is .51 mm.
• The cornea represents 25% of the rabbit eye surface area, but only 7% of the surface area in humans
• The rabbit epithelial (surface) layer is 10 times more permeable to hydrophilic solutes than the human eye.
• Bowman's membrane (the next layer) is six times thicker in humans than in rabbits
• The tearing system in rabbits is less efficient than humans
• Rabbits have a greater threshold for pain than humans, so irritating substances are not washed away easily
• In response to some toxic substances, humans develop corneal epithelial vacuoles but rabbits do not.

Due to the reports from such studies and mounting pressure from animal rights activists and consumers, there is a call for developing animal free testing alternatives.

Alternatives to the Draize Test

Efforts are underway to find safe alternatives to the Draize eye and skin tests. Some companies like Avon, Colgate-Palmolive, and Proctor and Gamble are switching to human cell based in vitro testing instead of relying on the Draize Eye test. For more information, please see Draize Eye Test Alternative

Alternatives to test skin irritancy are also being developed, using three dimensional cultured human skin models and also through in vitro testing. For more information, please see Draize skin test alternative

Both consumers and companies want safe products; however, animal testing is becoming an increasingly controversial topic. As a result companies are discontinuing testing on products and ingredients that have already been tested. Government legislations, such as proposed EU ban on animal testing on cosmetics will also help in significantly reducing animal testing.

See Also

Animal testing
BDIH
Leaping Bunny Program

References

• Product testing
• Ottawa Humane Society
• Animal rights online
• Anti vivisection society WA
• The Draize Test
• Of Mice, Models and Men: A Critical Evaluation of Animal Research By Andrew N. Rowan
• PETA
• The Draize Eye Irritancy Test
• Alternatives to animal testing
• The National Anti-Vivisection Society[[Category:Fashion And Beauty]